DESCRIPTION: (Adapted from Investigator=s Abstract) The World Health Organization estimates that 10 million HIV-infected individuals will die of tuberculosis (TB) during the decade of the 1990's. Although HIV-infected patients with TB respond to effective antituberculous therapy, their prognosis remains poor. Early deaths are often attributable to TB, but later deaths result from complications of HIV infection other than tuberculosis. Recent epidemiologic observations indicate that TB reduces survival and increases the rate of opportunistic infections in HIV-infected patients. Mounting evidence from immunologic and virologic studies supports the concept of co-pathogenesis in which immune activation triggered by tuberculosis, and mediated by cytokines such as tumor necrosis factor-alpha (TNFa), stimulates viral replication, increases viral load, and accelerates HIV infection.